Heretofore, it has been considered that a metabolic error of lipids in blood, such as triglyceride or cholesterol, is one of the major dangerous factors causing an abnormal increase in or imbalance of the level of lipids in blood, which results in arteriosclerosis as well as ischemic heart disease such as angina pectoris or myocardial infarction, and cerebral infarction.
As a medicine for hyperlipemia, clofibrate type medicine, nicotinic acid and derivative thereof have been mainly used so far. Although they reduce the level of triglycerides in blood, they are less effective in reducing the cholesterol. Further, probucol having a new structure or cholestyramine which is an anion exchange resin, has been used in recent years as the medicine for reducing the blood level of cholesterol, but they are contrarily inactive to the triglyceride.
The abnormal increase in the blood level of either triglyceride or cholesterol is a major factor in arteriosclerosis, in particular, artherosclerosis. It has especially been know that the risk of the onset of those diseases is remarkably increased if both types of lipids are increased simultaneously.
As described in the foregoing, although the medicines for reducing the level of triglycerides or cholesterol in blood have already been used clinically, it is further demanded to develop a more potent medicine which has little adverse reaction and is preferable also in the dosage, safety and application. In particular, much attention has been focused to the development of a medicine capable of effectively reducing both of the levels of triglycerides and cholesterol in blood together in view of the therapy and prevention of diseases caused by arteriosclerosis, such as ischemic heart disease and cerebral infarction, but no such medicine capable of satisfying these requirements has yet been found.